Hertz Mille Pro MPS 250 S4 / S2

Hertz Mille Pro MPS 250 S4/S2 - Shallow 10-inch subwoofer for extremely compact enclosures

The Hertz Mille Pro MPS 250 S4/S2 is a 10-inch shallow subwoofer that delivers high sound pressure and precise deep bass despite its shallow mounting depth. It was developed for ultra-compact, sealed enclosures and performs reliably where space is at a premium – for example, under the rear seat of many pickup trucks. The driver achieves approximately 20% greater mechanical excursion than conventional designs, thus offering a strong ratio of enclosure depth, low-end extension, and power.

Technical Highlights

• Ultra-flat mounting: 83.6 mm (3.35 inches)
• Power: 500 W RMS, 1000 W Peak
• +20% mechanical excursion compared to conventional designs
• Robust, screwless mesh grille included
• Optimized for extremely compact, sealed enclosures
• Stable cast aluminum basket design
• Non-vented rear design for reduced enclosure depth
• 38 mm (1.5 inch) six-layer copper voice coil for high thermal capacity
• Air Intercooling REvolution (A.I.R.) to prevent air compression
• Horizontal 8-AWG plug terminals
• Scan, discover, identify

Variant & Application

The MPS 250 is available as S4 and S2. Both variants are tuned for small, sealed enclosures from approx. 14 liters net and are ideal for shallow installations, e.g. under seats or behind trim panels. The centering with special support structure for spider and coil allows the magnet to be shifted further inwards – this reduces the overall height while maximizing linear excursion.

Technical Data (general)

• Size: 250 mm (10 inches)
• Power Handling: 500 W continuous, 1000 W Peak
• Impedance: 2 Ohm
• Mounting Depth: 82.6 mm
• Voice Coil Type: single
• Filter: no filter components in the subwoofer
• Voice Coil: Ø 38 mm (1.5 inches), 6-layer copper
• Frequency Response: 25 – 400 Hz
• Magnet Size (D x T x H): 134 x 55 x 36 mm
• Weight (per piece): 5.11 kg
• Magnet: high-density ferrite
• Cone: Polypropylene
• Xmech: 20 mm

Electro-acoustic Data MPS 250 S4

• Equivalent Diameter (D): 216.6 mm
• Xmax: 16.8 mm
• Re: 3.3 Ohm
• Fs: 29 Hz
• Le: 3.65 mH
• Mms: 234 g
• Cms: 0.11 mm/N
• B·l: 17.3 T·m
• Qts: 0.48
• Ns: 0.52
• Qms: 5.6
• SPL: 83.5 dB

Electro-acoustic Data MPS 250 S2

• Equivalent Diameter (D): 216.6 mm
• Xmax: 16.8 mm
• Re: 2.2 Ohm
• Fs: 28 Hz
• Le: 2.67 mH
• Mms: 250 g
• Cms: 0.13 mm/N
• B·l: 14.7 T·m
• Qts: 0.41
• Ns: 0.45
• Qms: 5.3
• SPL: 82.5 dB

Dimensions (physical)

• A: 274.5 mm
• B: 231.6 mm
• C: 103.2 mm
• D (Mounting Depth): 82.6 mm
• E: 244.6 mm
• F: 38.9 mm

Enclosure Recommendations

Sealed – tight and precise, high energy component from 20–40 Hz:

• Vb: 14.2 l net
• Fc: 49 Hz
• Qtc: 0.81
• Outer Dimensions (Example): W 386 mm, H 352 mm, D 160 mm
• Mounting Hole (M): 232 mm
• Wall Thickness: 16 mm

Panel Cut List – sealed:

• A: 386 x 352 mm – 2 pieces
• B: 386 x 128 mm – 2 pieces
• C: 320 x 128 mm – 2 pieces

Ported – for high output, focus on 40–80 Hz:

• Vb: 19 l
• Fb: 35.5 Hz
• Outer Dimensions (Example): W 713 mm, H 372 mm, D 130 mm
• Port/Inner Dimensions: Z 146 mm, P 98 mm, S 52.3 mm
• Mounting Hole (M): 232 mm
• Wall Thickness: 16 mm

Panel Cut List – ported:

• A: 713 x 372 mm – 2 pieces
• B: 713 x 98 mm – 2 pieces
• C: 340 x 98 mm – 1 piece
• D: 288 x 98 mm – 1 piece
• E: 495 x 98 mm – 1 piece

Installation & Compatibility

The MPS 250 S4/S2 fits into very shallow installation locations – for example, under seats or behind side panels. The non-vented rear allows for shallow enclosure depths, and the side 8-AWG terminals facilitate wiring. A screwless protective grille is included. For maximum control and precise bass, I recommend a small, sealed enclosure; if you want more output in the upper bass range and have space, choose the 19-liter ported tuning.